The present invention is directed to an infant swing, and more specifically to an open top, electrically driven infant swing which is stable and efficient in operation.
In the past there have been many different types of infant swings. In particular, very early on infant swings having an "A" frame configuration were very popular. In a typical swing configuration of this type, the swing structure consisted of two A shaped legs which were attached by a lateral cross bar or axle at the top vertices of the A. The swing itself was generally hung from the cross bar and a motor, usually either spring or electric, was operatively connected thereto to provide the motive force for moving the swing. In these prior configurations, the motor was usually located somewhere on one of the two leg structures, fairly close to the rotational axis of the axle. While this positioning of the motor was generally acceptable, it would be preferred, from a stability standpoint, to position the motor closer to the center of gravity of the swing, at a location generally equidistant from the respective support structures of the swing, namely the A shaped legs. An example of this type of prior art swing is shown in U.S. Pat. No. 5,378,196.
While swings of this general configuration have been popular, there are some disadvantages to these types of swings which have been addressed in more recent swing designs. In particular, while these prior art swings which incorporate an axle or crossbar to space the A shaped legs are relatively stable, the axle or crossbar tends to prevent easy access to a child located in the seat hanging therefrom. In order to overcome this problem, most of the newer swing designs tend to be "open top" designs wherein there is no crossbar or axle which runs directly across the top of the support structure over the top of the seat. These newer style "open top" swings allow much easier access to the child than the prior art swings discussed above. Examples of typical "open top" swings include U.S. Pat. No. 5,525,113 owned by Graco Children's Products, Inc., U.S. Pat. No. 5,769,727 owned by Evenflo Company Inc., and U.S. Pat. No. 5,791,999 owned by Kolcraft Enterprises, Inc. As can be seen in all of these patents, there is no axle or crossbar that extends directly over the top of the swing and stability is provided by attaching the bases of the A shaped legs, rather than the vertices of the A's as in prior art swings. While these designs have been generally effective, sometimes greater stability and rigidity than can be delivered by a swing structure having no upper crossbar or axle is desired.
Most importantly, though, it is noted that most prior art swing designs incorporate motor couplings which are directly linked to the swing itself. This type of design can successfully deliver power to the swing, but has some disadvantages. For example, the direct linkage means that if the swing is stopped or forced in the wrong direction while the motor is engaged, depending on the exact construction of the swing, the gears can be stripped or the motor can be damaged. Additionally, a direct linkage usually results in a swing motion which is rigid and fairly mechanical when it would be preferred to have a swing motion that is smoother and more pendulum like.
Accordingly, given some of the above-noted deficiencies of prior art infant swings, it would be desirable to have an infant swing including a support structure that is generally stable and allows easy access to an infant seated in the swing chair. Additionally, it would be desirable to have an infant swing that provides a novel drive and coupling system which efficiently provides a smooth, natural swing motion for an infant seated in the swing. Furthermore, it would be desirable to have a novel drive and coupling system which prevents damage to the swing motor and gear system when the motion of the swing is stopped or modified while the swing is in motion.